dracut-kdump.sh: POSIX doesn't support pipefail
    
    upstream: fedora
    resolves: bz2003832
    conflict: none
    
    commit 725027b735e6f27e51572c570b34c0c7186203ef
    Author: Kairui Song <kasong@redhat.com>
    Date:   Thu Aug 12 02:55:32 2021 +0800
    
        dracut-kdump.sh: POSIX doesn't support pipefail
    
        Set pipefail will cause POSIX shell to exit with failure. So only do
        that in bash.
    
        Signed-off-by: Kairui Song <kasong@redhat.com>
        Acked-by: Philipp Rudo <prudo@redhat.com>
    
    Signed-off-by: Tao Liu <ltao@redhat.com>